Formulation aspects and classification of monophasic liquids for Pharm.D I year

1. MONOPHASIC LIQUID
DOSAGE FORMS
Presented By
NARESH GORANTLA, M.Pharm.., (Ph.D)
Asso. Professor,
Balaji college of Pharmacy,
Anantapuramu

2. Contents
• Introduction
• Classification of Monophasic liquids
• Formulation Consideration

3. Introduction
• Monophasic dosage form refers to liquid preparation containing two
or more components in one phase system, it is represent by true
solution.
• A true solution is a clear homogenous mixture that is prepared by
dissolving solute in a suitable solvent.
• The component of the solution which is present in a large quantity is
known as “SOLVENT” where as the component present in small
quantity is termed as “SOLUTE”.

4. Advantages
• It is easier to swallow, therefore easier for children and old age people.
• Facilitate absorption of drug faster than solid dosage form as drug is
already in solution form.
• It is homogenous therefore give uniform dose than suspension or
emulsion which need shaking.
• Simple and fast to formulate
• It can be administered by various routes :
Oral, Parenteral (injection),enema for rectal use, otic (ear), nasal
and ophthalmic preparation.

5. Disadvantages
• They are bulky, so difficult to transport and store.
• Water is commonly use vehicle, which is prone to microbial growth.
So addition of preservative is needed.
• When expose to direct sunlight it may undergo hydrolysis, so need to
store in cool and dark place.
• Drug stability reduce by hydrolysis or oxidation. So, they have shorter
expire date than solid dosage form.
• Other major sign of drug instability are color change, Precipitation,
microbial growth etc.

6. Classification

7. Liquids meant for internal administration
• Syrup : Aqueous preparations of 60% to 85% sucrose with or
without flavoring agents and medicinal substances.
e.g. Chlorpheniramine maleate syrup, Chloral hydrate .
• Elixirs : Clear, aromatic, sweetened hydro alcoholic solutions
with or without medicinal substances, intended for oral use.
Eg: Dexamethasone elixir .
• Linctuses : Viscous, liquid and oral preparations that are
generally prescribed for the relief of cough.
Eg: Codeine Linctus.

8. Market available Syrup/Elixir/ Linctus

9. Liquids meant for external administration
Liquids used in the mouth
• Gargles :Aqueous solutions containing antiseptics or antibiotics
used to treat throat infections. Available in concentrated form with
direction for dilution with warm water before use. eg: Povidone
Iodine gargle.
• Mouthwash: Aqueous solution with a pleasant taste and odor used
to clean and deodorize the buccal cavity. Have antiseptic and
astringent activity.eg: Antiseptics-phenol derivatives.
• Throat paints : Viscous liquid preparation used for mouth and
throat infections. Eg: Phenol glycerine, Compound Iodine.

10. Market available Gargle, Mouthwash
and Throat paints

11. Liquids meant for external administration
Liquids instilled into body cavity
• Eye drops: Sterile, aqueous/oilysolutions intended for instillationin
To eye. Eg: Timolol maleate eye drops.
• Nasal drops Administered through the nose to obtain local effect.
Used during nasal congestion and upper-respiratory tract problem.
Eg: Oxymetazolin Hydrochloride nasal drops.
• Enemas: Aqueous or oily solution that is introduced into the
rectum and colon via the anus for cleansing, therapeutic or
diagnostic purposes.

12. Market available Eye drop, Nasal drop
and Enemas

13. Liquids meant for external administration
Liquid meant for skin
• Liniments : Oily liquid preparations, intended for external
application with rubbing action to the affected area. Use to relief
pain and stiffness, such as from muscles spasm and arthritis.
• Lotions : Topical preparation with a low to medium viscosity. Use
to moisturize dry skin. Eg: Calamine Lotion, baby lotion
• Paints : Solutions used to sterilize the skin.
Eg. Betadine antiseptic paint, Magenta paint

14. Market available Liniment, Lotion and
Paint

15. Formulation Consideration
• Solubility
• Stability
• Preservatives
• Pharmaceutical elegance
Viscosity modifiers
Sweetening agents
Flavouring agents
Colouring agents

16. Approaches to increase the solubility of the drug
 pH adjustment : By addition of buffer to the formulation .
 Co-solvency: By addition of water miscible solvent in which drug
has good solubility. The solvent known as co-solvent.
Micelle solubilization : At high concentration surfactant s are
forced into water to form colloidal aggregate known as micelle.
Drugs get adsorbed into micelle that increase drug solubility. Micelle
form only at critical micelle concentration.

17. Complexation: Drug-complexing agent complexation formed when
complexing agent is added to solution.
Micronization:
The process involve size reductionof drug particle 1 to 10microns
either by spray drying or fluid energy mill.
Hydrotrophy : Drug dissolve in the cluster of hydrotropic agent.
Also there is drug- hydrotrophy agent complexation formation to
increase drug solubility.

18. Preservatives
Preservatives must have following criteria:
• Effective against broad spectrum of microorganisms.
• Physically, chemicaly and microbiologically stable through
out the shelf life of the product.
• Non toxic, non sensitizing, soluble, compatible and with
acceptable taste and odour.
Types of Preservatives
• Acidic : phenol, benzoic acid, sorbic acid
• Neutral preservatives : chlorobutanol, benzyl alcohol
• Quarternary ammonium compounds : Benzalkonium
chloride

19. Stability
Chemical Stability
 Chemical stability of a formulation
is affected by:
 pH
 Temperature
 Ionic Strength
 Solvent effects
 Light
 Oxygen
Instability can be
prevented by use of:
o Buffering agents
o Antioxidants
o Proper packaging
(eg: use of amber bottle for
light sensitive products)
Physical Stability
 A stable formulation retains its
viscosity, color, clarity, taste, and
odour throughout its shelf life.
Objective
evaluation
 Colour can be measured
spectrophotometrically.
 Clarity can be
determined by
measurement of its
turbidity or light
scattering equipment.
 Viscosity can be
measured by use of
viscometers.
Subjective evaluation
 Taste and odour can be
determined either by
pharmaceutical
investigator or by a panel
of unbiased, taste sensitive
individuals.

20. Pharmaceutical Elegance
Viscosity modifiers
Sweetening agents
Flavouring agents
Colouring agents
Enhance viscosity. Eg: Povidone, hydroxyethylcellulose
To enhance palatability and mask the taste of the
drugs. Eg : Sucrose, saccharin, aspartame
Taste Sensation Recommended flavour
Salt Butter scotch, maple, apricot, peach, vanilla,
Bitter Wild cherry, walnut, chocolate, mint.
Sweet Fruit and berry, vanilla.
Sour Citrus flavours, liquorice, raspberry.
To enhance the appearance of the vehicle; which
matches well with the flavor employed in the
preparation .Eg: green with mint, brown with
chocolate flavor etc.

21. THANK YOU